Ultrasonographic Imaging of the Fetal Duodenal Tract

To investigate whether fetal duodenal tract sections can be visualized in the prenatal ultrasonographic examination.

This study was designed in cross-section. Healthy singleton pregnant women who applied to the perinatology outpatient clinic for second-level ultrasound scanning between September 2020 and February 2021 were included in the study. Demographic information of the participants was obtained and an ultrasound scan was performed. The fetal duodenal tract was evaluated in three sections, including the pylorus. The fetal duodenal tract was differentiated from adjacent organs by its anatomical location, hyperechoic nature, and presence of fluid in the lumen.

A total of 278 eligible participants between 18 and 22 weeks of gestation were evaluated. While the fetal pylorus was closed in 76.6% of the participants, it was open in 23.4%. Duodenum pars superior, pars descendens, and pars inferior imaging rates were 99.3%, 98.2%, and 95.7%, respectively. It was possible to distinguish these parts from neighboring organs by 99.6%, 100%, and 100%, respectively. While the first, second, and third parts of the duodenum were observed as solid in 42.0%, 58.2%, and 52.2%, respectively, 57.9%, 41.7%, and 47.7% had fluid in the lumen.

The fetal duodenal tract can be viewed with prenatal ultrasonography in pregnant women who are not in a dorsoanterior position. This may make an additional contribution to the diagnosis of duodenal obstructions, which is the most common cause of intestinal atresia in prenatal screening.